1. Field of the Invention
The present invention relates to a photographing (imaging) lens (lens barrel), more specifically to a mechanism thereof for supporting one or more optical elements and for guiding the same along the optical axis of the photographing lens.
2. Description of the Related Art
In a conventional lens barrel in which various elements thereof are installed inside a housing (stationary barrel) of the lens barrel that serves as an outermost wall of the lens barrel, a mechanism for supporting one or more optical elements such as a lens group and for guiding such optical elements along the optical axis of the lens barrel is entirely positioned in the housing.
Due to this structure, such a supporting and guiding mechanism becomes an obstacle to a reduction of the length of the lens barrel if the lens barrel is designed so that the length thereof becomes smaller in an non-operating state of the lens barrel than in an operating state of the lens barrel, i.e., if the lens barrel is designed to be a retractable lens barrel. Namely, the supporting and guiding mechanism makes it difficult to reduce the length of the lens barrel.